Spring arrangement for time fuses



Sept. 4,1945. q' d e 2,384,252

SPRING ARRANGEMENT FOR TIME FUSES Filed July 2, 1941 22 Fi .2 Fig.1 24 9 Gulno H'O'NGER 5V INVENTOR Patented Sept. 4, 1945 UNITED STATES PATENT:- OFFICE 2,384,252 t SPR ING ARRANGEMENT FOR-TIME FU SES Guido Hiinger, Geneva, Switzerland, assignorto Mefina S. A., Binningen, Switzerland, a corporation of Switzerland ,.Application July 2, 1941, Serial No. 400,841 In Switzerland August 26, 1940 3 Claims. (01'. 102+84 As is known, the application of a suspended wire-like balance-wheel torsion spring arranged along the axis of the projectile to clockwork time fuses for projectiles presents important advantages by comparison with the use of a spirally shaped balance-wheel spring and has already been carried out on repeated instances. It has been found, however, that the provision of such a spring is accompanied by the disadvantage that owing to the inertia prevailing when the projectile is fired ofi, transient or permanent distortions of the several parts of the clockwork mechanism may take place and these'may in turn cause permanent distortions of the balance-wheel spring. These obviously have an unfavorable influence upon the duration of oscillation of the balance-wheel and therefore on the operational accuracy of the entire clockwork mechanism.

Proposals have been made heretofore to obviate such distortions of the balance-wheel Spring. Thus for example it was proposed to secure one end of th balance-wheel spring to a resilient carrier. Another proposal consisted in so coupling with longitudinal movableness the spring of the balance-wheel to the axis of the latter that the operative length of said spring should keep the same value in spite of the distortion of the parts of the fuse or clockwork mechanism. However, such proposals are not simple to carry into practice, the more so as the entire fuse is of smaller overall size.

An object of the present invention is to provide by extremely simple means an improved balance-wheel torsion spring wherein proper equalization of the operative length of said spring is achieved while the clockwork mechanism is being made or when it is subsequently regulated.

Another object of the invention is to provide an improved balance-wheel torsion spring which while fulfilling the first-cited object afiords substantial unsensitiveness when the projectile fitted with the clockwork fuse thus equipped is fired off from the gun.

Still another object of the invention is to provide a tape-shaped or wire-shaped balance-wheel spring operating by torsion and having an undulated shape, so that it can without being damaged yield to slight distortions or small longitudinal shifts of one of its securing points with respect to the other parts of the clockwork mechamsm.

With these and such other objects in view as will incidentally appear hereafter, the invention comprises the novel structur and combination or arrangement of parts that will now be described with reference to the accompanying drawing exemplifying thesame and forminga part of the present disclosure. H

In thedrawing: j v Figur 1 is partly an elevational view and part.- ly'aIvertical sectional view showing oneform of the improved torsionspring as associated with parts of a clockwork mechanism adaptable to a time fuse for a projectile.

Figures 2,13 andxl are. fragmentary detail views showing other forms that may. be taken by. the torsion spring. r

As illustrated in Fig. 1, I0 designates the tapelike or wire-like torsion spring which has an une dulated or sinuous outline. The lowerend of the spring I0 is engaged in a slot formed in the upper end of an upstanding pin H and held in said slot byya thimble-shaped bush l.2.. The pin II is carried in a peripherally, groovedbearing 13; it has a stepped lowerenlargement 14' and forms the axis of an underlying balance-wheel, l5which is supported at somedistancefroma subjacent hollow carrier. or base L6. forming. the lower part of the .clockwork mechanism which may be of any conventional structure. The balance-wheel I5 is clear of the carrier [6 and may be held motionless during the transportation of the fuse by any conventional lock which is not shown as it forms no part of the invention. This will prevent any premature unwinding of the clockwork mechanism.

The bearing I3 is clamped in the apertured bottom of an upstanding tubular structure I! which forms the upper part or platen of the clockwork mechanism. In the smooth inner wall of this structure IT is telescopically engaged the bottom end of a carrying sleeve l8 while the outer Wall of said structure I! is screw-threaded as at Ila to match the inner screw thread of a retaining skirted nut l9 engaged over the externally screw-threaded wall 18a of the sleeve I8. Said wall l8c has a shoulder I by which any undue screwing down motion of the nut I9 is precluded.

Mutual rotation of the sleeve IS with respect to the tubular carrier structure I! after proper adjustment of the parts is prevented by a grub screw 20 whose shank projects through an adjacent longitudinal groove l8c formed in said sleeve and into contact with its outer wall as shown. The parts H and I8 are firmly clamped to each other on completion of their mutual adjustment by another grub screw 2| having a pointed bit engaging into a socket in the sleeve l8. Several screws such as 2! may be provided at different positions if required.

spring ID by a grub screw 23 forming the pper securing point for the spring ID. The top face of the sleeve [8 has a diametrical cut and a perip-heral shoulder defining a notch in which is accommodated a clamping 'ring; 24.'

Owing to the provision of the lining plate 22,

the spring I0 cannot be damaged by the shank of the securing screw 23 when the latter is driven home. '1

When assembling the parts, the distance between the points at which the torsion spring [0 isheldi at its ends may be varied by more or less screwing downtheskirted nut l9 upon the screwthreaded wall l8a of the carrier sleeve 18.. The required degree of accuracy may be obtained by providing the screw threads Ila and 18a, of opposite or differentiated pitch. .,When proper adjustment hasbeen secured,i the parts I! and I8 may be clamped together bydriving the screw 2|; into its socket.

Insteadof havingtheundulated or corrugated outline shown in Fig. 1,.thetorsion spring Ill may be rendered longitudinally resilient. by being looped or crooked intermediate its ends as shown byway of examples in .Figs..2; 3 and i.

In the modification shown in Fig. 2, the spring I0 is formed at any suitable position or positions intermediate its ends with a double counterelbow or S-shaped loop as shown at 25. In Fig, 3, the spring in is formed at any convenient position onpositions intermediate its ends with a substantially circular loop 26 situated in a plane more or less parallel to the. general direction in which the" spring extends. In Fig. 4. the spring I 0 is provided at any-convenient position or posi- 2,384,252 I I g tions between its ends with a substantially circular or polygonal loop 21 situated in a plane more or less perpendicular to the general direc tion in which the spring extends.

While only one of these loops 25, 26 or 21 has been shown, more than one may be provided in the length of the spring l 0 to render it adequately resilient lengthwise.

It will be understood that owing to the longitudinal resiliency possessed by the torsion spring stood that it is limited solely by the scope of the appended claims rather than by any of the constructional details set forth.

What is claimed is:

' 1. In a clockwork time fuse for projectiles, a balance wheel mechanism comprising a bearing, a balance wheel oscillatablein said bearing,- atorsion spring connected atone end to said balance wheel at the axis thereof, and a holding member mounted .inthe fuse opposite said balance wheel and to which member theother end of said torsion spring is connected, said torsion spring consisting of a. longitudinal wire having its mass lying substantially in the axis of torsion and having a configuration providing. predetermined limited longitudinal resilience greater. than that Of the wire itself.

2.. A balance wheel mechanism according to claim 1 in which the torsion spring is of undulatory configuration longitudinally between its points of connection' I 3. A balance wheelmechanism according to claim 1. in which thetorsion spring comprises straight portions at the ends thereof connected 0 to thebalance wheel and holding members respectively and at least one loop intermediate of said straight portions. GUIDO I-IONG'ER. 

